The Water Quality Association (WQA) and the National Onsite Wastewater and Recycling Association (NOWRA) maintain a joint task force on the issue of discharges from household water supply treatment systems to onsite wastewater systems.

While the group is working to identify specific questions to be answered regarding alleged effects of water softeners on wastewater systems, to reach consensus agreement on appropriate research and to obtain funding for research, they developed an “in-the-mean-time” guidance document for those who may currently have concerns about softeners and wastewater treatment on the same site.

The guidance says, “Both water softening/conditioning and onsite wastewater treatment systems are commonly used together, and in the majority of these cases no problems are indicated.” It also lists seven points of advice related to the topic:

 All onsite wastewater systems require maintenance on a regular basis to ensure proper function;
 Maintain your water softener system on a regular basis;
 The use of excessive bleaches & detergents, strong disinfectants, “every-flush” toilet disinfection chemicals and caustic drain cleaners should be avoided;
 Be sure to inspect your home for possible sources of excess water consumption such as leaking toilet flappers and valves;
 When selecting a new water softener, consider using equipment determined to be “high efficiency;”
 When installing new onsite wastewater equipment, consider the fact that some onsite system manufacturers require that water softener regeneration water not be discharged in their wastewater treatment systems; and
 If an issue arises and a water softener/onsite wastewater system interaction is suspected, inspect and assess the onsite wastewater system with a local expert on onsite wastewater systems and the water softener with a local expert on water softening/water conditioning systems.

The NOWRA board of directors approved the document in February and the WQA board of directors approved it on March 20, according to Joe Harrison, technical director of the WQA.